Governor



May 7, 1940. J. 5. JENNINGS. .u

GOVERNOR Filed Dec. 7, 1935 :s Sheets-Sheet 1 IN V EN TOR.

M 2 Qfl w I ATT RNEY5.

May'7, 1940. J. 5. JENNINGS. JR 2,200,065

' GOVERNOR Filed Dec. '7, 1935 3 Sheets-Sheet 2 I 'V I 14/;

ml 4g A gi INVE NTOR. Jkrrz's 5472772112145, 7

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AT RNEYS,

y 7, 1940- J. s. JENNINGS. JR .200.065

GOVERNOR Filed Dec. 7, 1935 3 Sheets-Sheet 3 INVENTOR.

A TTORNEYS.

Patented May 7, 1940 I UNITED STATES PATENT OFFICE GOVERNOR Jarvis S. Jennings, Jr., Detroit, Mich., assignmto Monarch Governor Company, Detroit, Mich., a corporation of Michigan Application December 7, 1935, Serial No. 53,347

15 Claims. (01. 137-153) This invention relates to governors for interstalled on an engine in connection with a downnal combustion engines and more particularly to draft carburetor. governors of the suction or vacuum operated Fig. 2 is a frag y Sectional p View Of type provided with a governing valve, such as a the V t e t u lines of 1 pivoted butterfly valve of either the balanced in the direction of the arrows.

01' unbalanced kind, actuated toward its closed 3 s a sect on taken through lines 3 o position in the intake passage by the operation 2 in the direction of the arrows of the engine. Fig. 4 is a bottom plan View of the governor.

An object of the invention is to provide a gov- 5 is a section taken through lines Of W; ernor of the foregoing class having a butterfly 2 in the direction of the arrows.

' valve eccentrically pivoted so as to unbalance 6 is section taken through nes -5 0f the same and wherein novel and improved anti- 2 in the direction of t e arrows. stealing means is provided which is elTective to 7 s de section taken t o lines prevent overrunning of the engine under relao F 6 in the d rection of the arrows. tively light load by manipulation of the carburet- 3 is a View similar to 3 but i us ra or throttle valve. i a m fi tion.

A further object of the invention is to pro- F 9 is a fr y p n V w, p r y in vide an anti-stealing device including a piston section, of the governor Shown in 3. subject not only to the pressures existing in the 1 Before explaining in detail the present i ill) intake passage above and below the valve but tion it is to be understood that the invention iS also preferably t th l cit of th fluid or not limited in its application to the details of gaseous i t fl in through th passage construction and arrangement of parts illus- A still further object of the. invention is to trated i the a pa y d aw s, since the prgvide an anti-stealing device peyafive prefinvention is capable of other embodiments and 1o erably as a result of differences in pressure above of being practiced Carried Ou in Var o W ysand below the valve and which is in turn opera- Also it is be understood that the p raseolo y tive to control the tension of the main govern- 0r terminology e p y herein is the P ing spring, as when. the carburetor valve is closed D Of description and net of limitatien, d i

under light load to overrun the engine. is not intended to limit the invention claimed .zo A further object is to provide a governor i herein beyond the requirements of the prior art.

which the governing valve, such as a pivoted In the embodiments of e v ntion illusbutterfly Valve of either the balanced or unbaltmted, by y Of example, in the drawings, there anced type is movable t @1056 by th operati n is provided a governor A for an internal combusof the engine and to open by the action preferation engine B adapted for use with a carburetor :23 bly of a simple straight-line spring, and in which C of the down-draft p Although designed for a rotatable crank arm acts on the spring to prothis purpose, it Will he understood that the vduce a disproportionately less deflection of the is equally adapted use in ect on spring as compared with the valve movement W an lip-draft calhuletor- As shOWn in Fig near the open position of the valve than near the 1, the carburetor throttle a v o t e convenvgo closed position thereof, and in which the effectinnel butterfly yp is indicated at D and is tive arm, through which the spring turns th erated manually in the usual manner to convalve shaft, is increased by maintaining the t1'01 the flow of a ous mixture through the inlength of the arm constant when it reaches its take p passage The ove or A s intermaxim'um posed in the intake. passage between the carbu- A further object of the invention is to provide retor thFottle Valve D and the intake manifold a simplified governor of the foregoing type capa F. The illustrated governor comprises a suitable ble of functioning with maximum eificiency and casing cast to provide projecting economy and Characterized by its Wide range of ears or bosses ll vertically drilled to provide bolt holes [2 for the reception of bolts lZa by adaptability to various engines or by its wide range of adjustabmty for any given engine or means of which the governor casing is attached m in position in the intake passage. In the position engmes' of the governor illustrated in Figs. 5 and 6, the other 019360135 of lnventlon W111, appear m carburetor C is located at the upper side of the the followmg descrlptlon and appended claims casing and the intake manifold at the bottom reference bemg had to the accompanymg draw side, there being an axial passage through the ings forming a part of this specification wherein casing which forms a t gf the intake passage like reference characters designate correspondh casing 10 i t, d machined 1; dig,- parts in the several VieWsmetrically opposed sides of the intake passage Fig. l is a side view of a governor constructed to provide interior recesses l3 which are herein 00 in accordance with the present invention and inshown as having parallel rectilinear side walls Lil I360. Within the recesses !3 are mounted a pair of adjustable inserts I l and which are preferably formed of metal suitable for die casting. The insert M is pivotally mounted at its upper end on a transverse pivot pin it driven into a hole drilled through the casing and removable therefrom for the purpose of changing or replacing the insert. The insert id in the present in stance is also pivotally mounted at its upper end on a transverse pivot pin 5 I, this pin being driven into a transverse drilled hole and likewise removable for the purpose of changing or replacing the insert. The upper end of the insert it is transversely slotted or grooved at it for the reception of a bowed leaf spring is, the ends of which project freely into notches Illa formed in the casing at opposite sides of the insert. In like manner, the upper end of the insert i5 is transversely slotted at to receive a similar leaf spring 23 having its ends confined within similar notches in the casing at opposite sides of the insert. Adjustment of the insert l4 about its pivotal axis it is obtained by means of an adjusting screw is! having a knurled head and a threaded shank extending obliquely through a tapped hole in the casing and engaging the upper end of the insert Hi. In like manner, adjustment of the insert l5 about its pivotal axis ll is obtained by a similar adjusting screw lilll engaging the upper end of the insert. The in-- serts, which form walls of the passage, are thus.

independently adjustable by means of the adjust-- ing screws and the adjustment of either insert is opposed by its spring It or 2!.

The inner vertical walls of the inserts I l and B5 are arcuate or concaved in formation and form with the side walls ita of the recesses l3 lateral enlargements of the intake passage in the governor casing. The enlargement of the intake passage intermediate the inlet and outlet orifices of the casing is accomplished by forming the insert M with an outwardly extended arcuate recess 25 arranged below the shaft l6 and forming the insert l5 with a similar recess 26 located above its pivot ll.

Mounted within the intake passage of the gov ernor casing ID is a governing valve 2? which is herein illustrated as of the butterfly type. The central portion of the valve is arcuate in shape and of a diameter to lit the corresponding arcuconform substantially to the curvature of the recesses 25 and 26 thereby permitting the valve to be moved into position, as shown in dotted lines in Fig. 6, to substantially close oi? the passage. The width of the valve in the direction of the inserts is, therefore, increased so that the valve in this direction is wider than the efiective diameter of the intake passage axially of the valve shaft. The valve, in the present instance, is shown as an unbalanced valve, being secured eccentrically to a cross-shaft 29 so as to provide a longer side 21a and a relatively shorter side 21b. It will be noted that the faces 28 of the valve blades are curved to produce a stream lined configuration.

The valve shaft 29 is journalled in suitable bearings at oppcsite'sides of thecasing and pr'o jects laterally through a hole in one side wall of a casing Eilll secured to the valve casing Ill.

Fixed to the outer end of this shaft is a sleeve 30 provided with a laterally projecting crank arm 3i terminating in a shoe 32 having an outer curved bearing face. The lower edge of this shoe is bifurcated to receive a transverse pin 32a to which is attached a length of steel tape 33. The band or tape 33 is also attached to one end of a tension spring 34,. the other end of which is anchored at 35 to the short arm 36a of a lever 33% pivoted at 3'! to the outer end of an adjusting member 38. The latter has a sliding fit in a boss 38a of the casing and its end is drilled and tapped to receive the threaded shank 39 of an adjusting screw All. By adjusting'thisscrew the member 38 may beadjusted within the boss 38a so as to vary the position of the supportingpivot 8'! for the lever 36. screw is housed within a housing or boss 4i.

outer end at d2 to a connecting rod Q3 and the inner end of the latter is pivotally connected by I means of a wrist pin to a piston 44. The piston has a sliding fit within the cylindrical bore of a barrel or cylinder 65, one end ofwhich is open to the interior of the casing 200 which in turn has a cover or closure plate 29! completely sealing the casing from the atmosphere. At the opposite side of the shaft 29 from the crank arm 3! the sleeve Ell is provided with a projecting member 46 forming a counter-weight.

The interior of the casing 280 is subject to the pressure in the intake passage existing at a suitable point between the valve 2"! and the carburetor throttle valve, and accordingly a hole dl is drilled through the walls of the casing to provide a passage opening into the main intake passage at a point well above the valve axis. The passage .1, see Figs. 6 and '7, is extended into the intake passage by means of a short section of tubing 4-8 which has a right angle bend with a lateral opening 49 facing upwardly or toward.

the carburetor throttle valve. The tube 48; therefore, is in the nature of a Pitot tube, being positioned within the intake passage so that its fiaring open end 49 will be directly exposed to the flow of fluid. Hence, by reason of the velocity of the fluid in the intake acting on the column of air in the tube, the static pressure in the casing 2% will be increased or built up. The closed end of the piston chamber i5, and hence'the outer end of the piston 44 is subjected to the pressure in the intake passage existing at a point between the governing valve and the intake manifold. This is accomplished by means of. a pipe 50 leading from the closed end of the piston chamber and communicating with a passage El drilled through the side wall of the casing Ill:

and opening in the passage, as shown in Fig. 6, at a point well below the valve axis. At a point slightly above the valve axis which is traversed by the valve when moved from open to closed position is a bleeder port 52 opening into the intake passage through the wall of the casing and connected by means of communicating passages 53 and 54 with the main vacuum passage The bleeder passage is controlled by means a munication between the bleeder passages 52-44 and vacuum passage 5!.

Referring to the embodiment illustrated in,

Figs. 8- and 9, in'this instance the constructionof the governor is identical with that illustrated in Figs. 1 to 7 inclusive with the exception that the counter-Weight 46, fixed to the valve shaft 29 in the previous embodiment, is omitted. In this instance the sleeve 30, which is pinned or otherwise fixed to the valve shaft, is provided with a projecting arm 51 located at the opposite side of the valve shaft from the crank arm 3|. An auxiliary spring 59, substantially lighter than the spring 34, is interposed between the arm 51 and the long arm 36b of the lever 36. This spring is connected to pins 58 and 60 projecting respectively from the sides of the arms 5'! and 36b in such manner, as shown in Fig. 8, that the axis of the spring intersecting the points 58 and 60 will lie below the valve axis when the valveis in wide open position, at which time the spring will exert a force tending to hold the valve in open position.

It will be seen in this embodiment that when the governing valve is in its Wide open position, as shown in full lines in Fig. 8, the tension of the auxiliary spring 59' acts upon the valve shaft through a very small effective arm, acting at the same time upon the main spring .34 with a much greater arm. Thus, the auxiliary spring 59 exerts a slight force upon the governing valve when the valve is wide open, tending to hold it in this position. This opening force diminshes to a zero value when the arm 51 reaches its dead center position. During this closing movement from wide open valve position the crank arm 51, after a travel of approximately 15, passes through its zero value, during which time the crank arm 3! will have rotated sufficiently to stretch or elongate the main spring 35. As the arm 57 continues in a counter-clockwise direction past dead center, and during a considerable portion of this travel, the spring 59 will be maintained under sufficient tension to exert a substantial turning effort on the lever 36 not only assisting in holding the arm 36a of the lever and hence the piston in its fully retracted position but also exerting a closing effort on the valve.

It, therefore, follows that at the wide open po sition of the valve the auxiliary spring 59 through crank arm 51 exerts an opening effort on the valve which effort diminishes to zero as the crank arm rotates to its dead center position, the moment of the spring force in this direction being greatest when the valve is fully open. After the crank arm 57 passes dead center, however, the spring exerts through this arm a closing effort on the'valve which effort gradually diminishes to zero value as the governing valve approaches its closed position. It will be seen that the maintenance of the retracted position of the piston is assisted by the auxiliary spring 59. When the governing valve is closed, there is substantially no deflection of the auxiliary spring. But as, the valve opens under the influence of the main spring, the tendency of the piston to be displaced, due to the pull of the main spring, is progressively offset by the stretching or elongation of the auxiliary spring, the effect of which is transmitted through the longer arm of the lever 36.

In the operation of the governor it will be unintake passage will be relatively slow and the difference. in pressures above and below the governing valve will be slight. Under such condi-' tions only a very slight force is necessary to maintain the governing valve in its Wide open position, and since the effort exerted by the main spring 34 at this time is negligible, the counterweight 46 is utilized to provide this opening effort. In the embodiment illustrated in Figs. 8 and 9, the action of the counter-weight to produce this result is accomplished by the light auxiliary spring 59.

The valve '21 is, of course, maintained, as by means of a suitable stop, in a slightly inclined position as shown in Figs. 5 and 6, whichposition is due in part to the fact that the valve is streamlined and also offset in twov planes. When the valve is in this wide open position, there is a substantial closing torque on the valve resulting from the force due to the velocity of the fluid and also to local pressure differences which are augmented by reason of the stream-lined form of the valve. As the engine speed increases and due to this slightly inclined position of the valve and the offset thereof, two phenomena occur in the closing of the valve by the operation of the engine. The moving fluid strikesv the valve and tends to close it. In addition to the foregoing, due to the fact that the valve creates an obstruction in the passagathe pressure at the carburetor side of.

the valve rises and the pressure at the engine side drops as the valve moves toward closed'position. By virtue of this, differential in pressure and the unbalance of the valve, a closing force is exerted on the valve inaddition to the force due to the'velocity of the fuel mixture. It will be understood that while the force, due to the velocity of the fluid, diminishes as the valve closes, the force, due to static pressure differences, increases very rapidly as the valve approaches its closed position. In the presentemboclimentsof the invention, the principal means for resisting the closing forces on the valve is in the form of a sin- .gle straight-line spring3 l, and the construction is such that the closing forces on the valve, 1. e. the closing moments on the valve shaft, are resisted by the spring up to the maximum permissible speed, and at the set speed the opening and closing moments on the valve shaft are substantially equal.

In its preferred forms, the operation of the governor, by which the opening or resisting moments produced bythe spring are caused to balance the closing moments produced by the action of. the fluid or vacuum on the governing valve, is produced in three ways: (1) by increasing the closing moment produced by the action of the fluid on the governing valve 21 during the early closing movement of the valve;-

(2) by decreasing the closing moment produced by the action of the vacuum on the governing valve when the latter is approaching its closed position, and (3) by balancing the resistance force and, consequently, the opening moment produced by the spring 34 against the closing effort of the valve throughout the range of travel of the valve.

The increase in the by the action of the fluid on the governing valve is achieved by shaping the valve so as to have a stream-lined configuration and by increasing the size or area of the valve. In stream-lining the valve, as shown at 28, it is made of such a cross-section that the passage, formed'between the valve surfaces and the walls of the conduit, operates to prevent turbulences and to produce non-turbulent flow of high effect, thereby increasing the velocity force acting on the valve by decreasing the static pressures past the end closing moment produced valve.

duces a greater rate of closing of the valve for a portions of the'valve. By increasing the size or area of the valve, it is possible to amplify the effect of velocity force and vacuum force produced as a result of the stream-lined shape of the The increase in length of the valve prothe valve 2? is approaching its closed position, is

accomplished by controlling the effective opening of'the valve through the medium of the insert walls It and 15, the construction and operation thereof, together with their advantages, being particularly shown anddescribed in my copending application Serial No. 46,989, and in these respects reference is made to said copending application.

The balancing of the resistance force of the spring 34 against the closing eifort of the valve throughout its travel is in the present instance accomplished in three ways: (1) by increasing the total deflection of the spring 3%; (2) by increasing the effective arm through which the spring acts upon or turns the valve shaft 29 and by maintaining the length of the arm 3! constant when it reaches its maximum, see dotted line position in Fig. 3; and (3) by the action of the counter-weight 46 or the auxiliary spring 59.

It will be understood that during any intermediate engine speed, the closing of the governing valve 21 will turn the crank arm 35 thereby stretching or elongating the straight-line spring 3%. By providing the rotating crank arm 3!, it will be seen that the distance to which the spring is stretched, or the deflection thereof, is made non-proportional to the angular movements of the governing valve. is initially moving away from its open position, the arm 3! moves nearly perpendicularly to the spring axis and, therefore, stretches the spring but slightly. As the crank arm iii, however, moves toward the dotted line position shown in Fig. 3, the distance through which the spring as is stretched or deflected per unit of angular movement of the governing valve increases, and when the crank arm reaches the dotted line position, the elongation of the spring per unit of angular movement of the crank arm or valve and the moment of the spring force reach their maximum. Ordinarily, upon passing this position,

the reverse action of the spring takes place.

In accordance with one aspect of the present invention, means is provided for maintaining the elongation of the spring 34 as also the moment of the spring force at its maximum, as shown in dotted lines in Fig. 3, after this point has been reached. Thus, as the crank arm 3i" moves further to the right from the dotted line position,

reached the dotted line position in Fig. 3, are

When the valve eliminated. As a consequence of this feature-off the invention, combined with the actionof 'th'e' counterweight or the auxiliary spring, it is possible to permit the governing valve to move through a greater anglethan 99, i. e. as much'as 120, without losing the. final effective resistance force of the spring. The lower deflection rate made possible by'the greater arc of travel of the M, it will be seen that the effective tensionof the spring at any time is dependent uponthe' position ofv the'piston in its cylinder and hence the position of the lever 35. Withthe piston held in the position shown in Fig. 3, the spring will be capable of exerting its maximum resist ance to the closing of the valve, but any movement of the piston to the left will efiect arelaxation of the spring tension. During operation it will be understood that a balance between the opposed forces'of the spring and piston on the lever will be reached at all times. mal governing operation, with the carburetor valve wide open, the pressure in the casing 2M1 acting on the inner end of the piston, which pressure is increased by the effect of the tube'48, must be sufiicient to hold the piston retracted as in Figs. 3 and 8. It is, of course, essential-during governing conditio-ns that the piston beheld in-fully retracted" During norposition, see Fig. 8, regardless of the position of i the governing valve. If the piston has such a size or efiective area that it will just barely over balance the pull of the main spring 34 when the governing valve is in no-load or substantially closed position, it will not have large enough area to exert sufficient force to hold the lever arm 36b fully retracted against the pull of the main spring. when the valve is nearly open, i. e. in any of those.

positions of the valve when the velocity forces become a factor and the force due to static pressure differences is small. Although under such conditions the Pitot tube eifect of the member 18, by increasing the pressure in the casing 200,

assists in holding the piston retracted, yet it has been found desirable to supplement this.

Therefore, the piston 34 is made slightly larger than necessary to maintain a balance against the main.

spring at no-load position. By this slight increase in the piston area it is capable of exerting sumcient force, assisted by the effect ofthe velocity tube &8, to maintain a balance against the main spring at near-open positions of the valve. In order, however, to compensate for this increase in piston area or oversize of the piston (which is beneficial when the valve is in its openpositions as above explained) the adjustable air bleed 52' into the main vacuum line 5B 5l is provided,

the bleed 52 being opened or exposed to the higher pressure at the carburetor side of the governing valve at a predetermined time when the latter;

approaches no-load position.

,The anti-stealing device, in the present in-' stance, is such as to be very sensitive, responding to stealing attempts under all conditions, particularly when the carburetor valve is partiallyclosed and attempt is made to overrun the engineunder a very light load. When the carburetor throttle valve is partially closed, the pressure in the intake passage between the carburetor and governing valves drops, thus reducing the difierence in pressure between the up and down stream and governing valve.

sides of the governing valve acting on the piston 44. As a consequence of the reduction in the closing effort on the governing valve under such conditions, the main spring 34 normally would tend to overbalance the closing effort on the valve thereby causing it to open and hence speed up the engine. This, however, is obviatedin accordance with the present invention. The operation of the piston 44 in the present governor is such as to decrease or relax the tension of the main spring 34 under such conditions so as to cause the governing valve to close despite the fact that the effective vacuum action or effort Onthe governing valve is decreased.

Assuming. that a condition of balance exists between the main spring, governing valve and piston during normal governing operation, if the carburetor valve is partially closed by the operator and manipulated for the purpose of-stealing, the pressure in passage 41 and in the casing 200 will be reduced due to the reduction in pressure in the intake passagebetween the carburetor This will effect a reduction in the pressure on the inner end of the piston which pressure, it is assumed, was theretofore sufficient to hold the piston extended and balanced against the main spring tension. As a consequence the piston will move to the left under the pull of the main spring on the lever 36 until a balance is reached, but this action results in relaxing the spring force acting through crank arm 3| on the governing valve. By thus reducing the spring resistance, the governing valve will close in accordance with the closing of the carburetor throttle valve. It will be noted that the insert M with its con- 1 toured portion of the intake passage is pivoted somewhat past orbeyond the point where the adjacent portion of the valve2'l normally comes to rest at no-load position, as shown in dotted lines in Fig. 6. Hence, adjustment of this insert toward the valve results in a diminishing rate of increase in the effective opening as the valve swings open andhence a lower governed speed,

and conversely adjustment of insert I4 away from' the valve produces a higher rate of increase in the effective valve openings as the valve swings open and hence a higher governed speed. The insert IS, on the other hand, with its contoured portionof the passage is in the present instance pivoted in advance of the point where the adjacent portion of the governing valve normally comes to rest at no-load position. By thus mounting the insert l5 in this manner a greater r range of adjustment at the idling position of the governing valve is possible, since adjustment of this insert about its axis I1 primarily increases or decreases the effective opening at or near the idling r no-load position shown in dotted lines in Fig. 6.

It will be understood that the contour of the walls 25 and 26 of the inserts may be widely varied, and although but an approximate 90 travel of the governing valve is indicated in the drawings, it will be understood that by varying edges of the blade portions 21a and 2111 are the of spring and vacuum forces is assisted at this time by varying the rate of deflection or movement of the spring 34 through the angularity of the crank arm 3 I, as previously described. Thus, near wide open position there is obtaineda large angular movement of the valve for a slight deflection of the spring. As soon as a point isreached in the valve travel when the disproportionate relationship: due to the angularity of the crank arm 3| disappears, as at the dotted line position shown'in Fig. '3, the balance of the forces is to a substantial extent achieved by shaping the walls 25 and 26 so as to produce the areas of effective valve opening calculated to induce the manifold pressures necessary to balance the spring loads at all points in the range of closing travel of the valve. Hence, as the governing valve nears its closed position, the differential action due to the angularly shaped walls '25 and 26 produces a disproportionately small valve movementas compared with the movement or deflection of the spring. It might be said in this respect that the vacuum curve is thus modified so as to conform to the spring curve.

I claim: v

1. A governor for an'intern'al combustion engine comprising an unbalanced governing valve movable towards closed position by the operation of the engine, a spring opposing said movement, an anti-stealing device for exerting a closing effort on the valve and actuated both by static pressure in the intake manifold and the velocity of thefiuid flowing through said passage, and means for augmenting the'action of the main spring at wide open valve position but substantially ineffective at its closed position.

2. A governor for an'int'ern'al combustion engine comprising an unbalanced governing valve movable towards closed positionby the operation of the engine, a spring opposing said movement, an anti-stealing device for exerting a closing effort on thevalve and actuated both by static pressure in the intake manifold and the velocity of the fluid flowing through said passage, and an auxiliary spring for augmenting the action of the main spring at wide open valve position but substantially ineffective at its closed position.

' 3. A governor for an internal combustion engine comprisinga governing valve movable toward closed position by the operation of the engine, a spring for resisting closing movement of the valve, a shaft upon which said valve is mounted to turn, a crank arm through which said spring turns the valve shaft and having an increasing eifective arm as the valve moves from open toward closed position, and means for rendering said effective arm constant upon reaching its maximum effective length.

' 4. A governor foran internal combustion engine comprising a casing having an intake passage therethrough and inlet and outlet portions,-

a governing valve in said passage pivoted on an eccentric axis to provide an unbalanced condition and movabletoward closedposition by :the operation of the-engine, said passage intermediate said inlet :and outlet portions .being widened in the direction :of closing of the valve at 'one side above the valve axis and at the opposite side 'below the valve axis to provide curved contoured surfaces swept by the outer. edges of the valve.

5. A governorfor an internal combustion engine comprising a casing having an intake passage, a butterfly valve in said passage pivoted eccentrically. to provide an unbalancedcondition, av spring resisting closingmovement of said valve, the wallof said casingat-each sideof the valve axis having arecess cooperating with an edge of the valve and providing a progressive widen.- ing of the :passage in the directionof closingof said edge of the valve, the maior'portion'of one of'said recesses being: above the valve'axis and the major :portion-of the other =recess being *below the valve axis and the wwalLof each recess sloping inwardly'toward the Wide open position oftheadjacent cooperating valve edge.

6. A governorfor an internalcombustion engine comprising a casing having an intake pas sage,: an unbalanced butterfly valve in said passage, a spring resisting closing movement of said valve, means interposed between said spring and valve "for causing near the open position of the valve a less movement of the spring as compared with the movement of the valve,xthe walls of said valve passagebeing contoured to produce pressure in the'passage for controlling the ten sion of said spring relatively to the valve.

'7. In a governor for internal combustion engines, a casing having :an intake passage, a governing valve in said passage 'eccentrically mounted to provide an unbalanced condition :and movable toward'closed position by the operation of the engine, a spring opposing said closing movement, means for varying the rate of spring deflection as compared with the valve movement, separate means'for varying the rate of eflective closing movement of the valve'ias compared with the rate of spring deflection, and vacuum responsive means ior controlling the tension of said spring relatively to the valve.

8. A governor for an internal combustion engine comprising an unbalanced governing valve movable toward closed position bythe operation of the engine, a spring opposing said closing movement, a piston connected to the valve and disposed out of the path of flow of the fluid in the intake passage, said piston being subject to the difference in pressures at opposite sides of the valve, and means for decreasing such efiective difference at a predetermined point inthe closing travel of the valve.

9. A governor for an internal combustion engine comprising an unbalanced governing valve movable toward closed position by the operation of the engine, a-spring opposing said closing movement, a piston connected to the valve anddisposed outof the path of flow of the fluid in the intake passage, said piston being subject to the diflerence in pressures'at opposite sides of the valve, means for decreasing such diflerence at a predetermined point in the closing travel of the valve. and means for subjecting said piston'to the velocity force of the fluid flowing through the intake passage.

10. A governor for an internal combustion engine comprising a governing valve -movable to- :ward closed position :by "the operation :of the .engine,;a: spring opposinggsaid closing movement,

.-a pistoniconnectedztothe valve and disposed-out of the path of flow-of the fluid. inthe intake passage, said piston being subject to the differ-- ence, in pressure at-opposite sides oithe valve,

and .means .for varying such :diflerence :atva predetermined :point in the travel of the valve.

11. A governor for an internal combustion engine having an intake-passage, comprising a pivoted unbalanced butterfly governing valve mounted insaidpassageiand adapted tobe partially rotated toward closed position by the opera-. tion of the engine, spring meansa'esisting said closing :movement and adapted to substantially balance theclosing effort on the valve at different positions thereof during governing operation, and

means.

:12. A governor for an internal combustion enginehaving an intake passage, comprising a pivoted butterfly governing valve mounted in said passageand-adapted'to be partially rotated toward closed position by the operation of the engine, a spring resisting said closing movement andadapted-to substantially balance the closing e'fiort on-the valve at diflerent positions thereof,

and a vacuum actuated device subject to the pressure in said passage upstream of the governing-valveand acting upon said spring to render the spring-ineffective at a predetermined time to "impart an opening movement to the valve, saidspring being connected at one end to the valve and at its opposite end to the device.

'13. -A governor for an internal combustion engine having-an intake passage, comprising an unbalanced governing valve in said passage movable towards closedposition by the operation of the engine,-a spring opposing said movement,f ananti-stealing device for exerting a closing e'fiort on'the'valve andsubject to the pressure in said passage upstream of the valve, and a lever connecting "said device and spring for transmitting a force from said device to the spring.

14. A governor for an internal combustion engine having an intake passage, comprising an unbalanced governing valve insaid-passage mova 'ble towards closed position by the operation of the engine, a springopposingsaid movement,'an antistealing device for exerting a closing effort-on the'valve and subjecttopressure in said passage; and a leverconnecting said device andspring for transmitting a force from said device to" the spring, said lever being fulcrumed' intermediate its ends and having a shorter arm connected to the spring anda longer arm-connected to the movement while the valve is closing effective to,

produce a disproportionately greater deflection of the-spring near the closed position of the valve than near its open position, and a'member on the outer end of said crank arm adapted to engage said flexible member only after said angular movement of the valve.

JARVIS s. JENNINGa-JR; 

